Plate-type heat pipe and method for manufacturing the same

ABSTRACT

An exemplary plate-type heat pipe includes a condensing plate, an evaporating plate and a spherical supporting. The evaporating plate engages with the condensing plate to define a hermetic container. Working fluid is contained in the container. The supporting portion in the container is sandwiched between the condensing plate and the evaporating plate and abuts against the condensing plate and the evaporating plate.

BACKGROUND

1. Technical Field

The present disclosure relates to plate-type heat pipes, and moreparticularly, to a plate-type heat pipe having stable and reliableperformance and a method for manufacturing such plate-type heat pipe.

2. Description of Related Art

Generally, plate-type heat pipes are used to absorb heat generated byelectronic components and transfer and/or dissipate the heat elsewhere.A typical plate-type heat pipe includes a plate-shaped container, a wickstructure formed on inner surfaces of the container, and working fluidsealed inside the container. The container is prone to be deformed whenit is pressed accidentally or when the working fluid is vaporized,thereby adversely affecting the stable performance of the plate-typeheat pipe.

What is needed, therefore, is a plate-type heat pipe which can overcomethe limitations described, and a method for manufacturing such aplate-type heat pipe.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded, isometric view of a plate-type heat pipe inaccordance with an embodiment of the present disclosure.

FIG. 2 is an assembled, side cross-sectional view of the plate-type heatpipe of FIG. 1.

FIG. 3 is a side cross-sectional view showing a first mold accommodatinga condensing plate of the plate-type heat pipe of FIG. 1.

FIG. 4 is similar to FIG. 3, but showing a first wick structure of theplate-type heat pipe of FIG. 1 being formed on the condensing plate.

FIG. 5 is an isometric view of a first mold portion of a second mold,which is used for forming a second wick structure of the plate-type heatpipe of FIG. 1.

FIG. 6 is an isometric view of a second mold portion of the second mold,showing the second mold portion inverted.

FIG. 7 is a side cross-sectional view showing the first and second moldportions of the second mold coupled together and accommodating anevaporating plate of the plate-type heat pipe of FIG. 1.

FIG. 8 is similar to FIG. 7, but showing a second wick structure of theplate-type heat pipe of FIG. 1 being formed on the evaporating plate.

DETAILED DESCRIPTION

A method for manufacturing a plate-type heat pipe in accordance with anembodiment of the present disclosure includes steps of: a) providing afirst metallic sheet, a second metallic sheet, and a supporting portion;b) arranging the supporting portion between the first metallic sheet andthe second metallic sheet; and c) welding the first and second metallicsheets together, thereby obtaining a hermetical container, thesupporting portion abutting against and connecting with the first andsecond metallic sheets. Exemplary details of the method are given below.

Referring to FIGS. 1-2, in a typical application, the method is used tomanufacture a plate-type heat pipe which includes an elongatedcondensing plate 11, a tray-shaped evaporating plate 13, a first wickstructure 12, a second wick structure 14, and a plurality of supportingportions 15. The condensing plate 11 hermetically contacts theevaporating plate 13. The evaporating plate 13 is adapted for absorbingheat generated by one or more components (not shown) such as electronicdevices. The condensing plate 11 dissipates heat, transferred from theevaporating plate 13, to the ambient environment. The first wickstructure 12 is adhered on an inner surface of the condensing plate 11.The second wick structure 14 is adhered on an inner surface of theevaporating plate 13. Each of the supporting portions 15 is a sphere andabuts against the inner surfaces of the condensing plate 11 and theevaporating plate 13, respectively. The condensing plate 11, theevaporating plate 13 and the supporting portions 15 are formed frommetallic material which can be soldered and which transfers heat well.In this embodiment, the condensing plate 11, the evaporating plate 13and the supporting portions 15 are made of copper.

The evaporating plate 13 includes a rectangular heat absorbing portion131, four sidewalls 133, and two extending portions 135. The sidewalls133 perpendicularly extend upwardly from four edges of the heatabsorbing portion 131. The extending portions 135 extend outwardly alongopposite horizontal directions from top portions of two oppositesidewalls 133, respectively. The extending portions 135 areperpendicular to the sidewalls 133. Top surfaces of the extendingportions 135 and top ends of two corresponding sidewalls 133interconnecting the extending portions 135 are all coplanar with oneanother.

The second wick structure 14 includes a first wick portion 141 and foursecond wick portions 143. The first wick portion 141 is adhered on aninner surface of the heat absorbing portion 131. The second wickportions 143 are adhered on inner surfaces of the sidewalls 133,respectively. The top surfaces of the extending portions 135 and the topends of the two corresponding sidewalls 133 hermetically connect aperiphery of a bottom surface of the condensing plate 11. Four lateralside edges of the first wick structure 12 connect with inside surfacesof top ends of the second wick portions 143 of the second wick structure14, respectively. The supporting portions 15 extend through the firstwick structure 12 and the first wick portions 141 to directly abutagainst the condensing plate 11 and the heat absorbing portion 131 ofthe evaporating plate 13, respectively.

Referring also to FIGS. 3-4, the first wick structure 12 is sinteredcopper powder made in a first mold 20, and the second wick structure 14is sintered copper powder made in a second mold 40, as shown in FIGS.5-8.

The first mold 20 includes a first mold portion 21, and a second moldportion 23 matching with the first mold portion 21. The first moldportion 21 includes a top plate 213 and four elongated, spaced pressingwalls 215 extending perpendicularly downwardly from an inner surface ofthe top plate 213. The second mold portion 23 is a rectangularcontainer, and includes a supporting plate 231 and four baffling plates233 extending perpendicularly upwardly from four edges of the supportingportion 231. A space (not labeled) is thus defined among the bafflingplates 233 over the supporting plate 231.

The condensing plate 11 is received in the second mold portion 23, withlateral side edges of the condensing plate 11 abutting against innersurfaces of the baffling plates 233. Top ends of the baffling plates 233protrude up beyond the condensing plate 11. The first mold portion 21 iscoupled to the second mold portion 23, with the pressing walls 215received in the space and engaging with inner sides of the bafflingplates 233, respectively. The top ends of the baffling plates 233 abutagainst a periphery of the inner surface of the top plate 213. In such astate, bottom ends of the pressing walls 215 contact peripheral portionsof the condensing plate 11. The pressing walls 215, the top plate 213and the condensing plate 11 cooperatively define a rectangular firstreceiving chamber 30.

The copper powder is filled in the first receiving chamber 30 and issintered to form the first wick structure 12 on a main central portionof the inner surface of the condensing plate 11.

The second mold 40 includes a first mold portion 41 and a second moldportion 43. Referring to FIG. 5, the first mold portion 41 includes anengaging plate 413, and a cuboid protruding portion 415 protruding froma central portion of the engaging plate 413. Therefore each of oppositelateral ends of the engaging plate 413 exposed beyond the protrudingportion 415 forms a first pressing portion 414, and each of two oppositefront and rear ends of the engaging plate 413 exposed beyond theprotruding portion 415 forms a second pressing portion 416. A size ofeach first pressing portion 414 is larger than that of the correspondingextending portion 135 of the evaporating plate 13. A size of each secondpressing portion 416 is larger than that of the top end of thecorresponding sidewall 133. A plurality of cylindrical receiving holes4151 is defined in the protruding portion 415 to receive the supportingportions 15 therein. A height of the protruding portion 415 is less thana height of the sidewalls 133 of the evaporating plate 13. A length ofthe protruding portion 415 is less than a distance between the twocorresponding sidewalls 133 of the evaporating plate 13. A width of theprotruding portion 415 is less than a distance between the twocorresponding sidewalls 133 of the evaporating plate 13. A diameter ofeach receiving hole 4151 is substantially equal to or slightly greaterthan a diameter of each supporting portion 15, and a depth of thereceiving hole 4151 is less than the diameter of the supporting portion15.

As shown in FIG. 6, the second mold portion 43 includes a supportingplate 431, two first extending plates 433 and two second extendingplates 435. The first extending plates 433 are elongated, parallel toeach other and extend upwardly from two opposite front and rear ends ofthe supporting plate 431. The second extending plates 435 are elongated,parallel to each other and extend upwardly from two opposite left andright lateral ends of the supporting plate 431. The second extendingplates 435 perpendicularly interconnect the first extending plates 433.A height of the second extending plates 435 is less than that of thefirst extending plates 433. The difference between the heights of thesecond extending plates 435 and first extending plates 433 is generallyequal to a thickness of the extending portions 135 of the evaporatingplate 13. The supporting plate 431, the first extending plates 433 andthe second extending plates 435 cooperatively define a receiving chamber437 to receive the evaporating plate 13.

Referring to FIGS. 6 and 7, to form the second wick structure 14, theevaporating plate 13 is received in the receiving chamber 437 of thesecond mold portion 43 of the second mold 40, with the heat absorbingportion 131 of the evaporating plate 13 contacting the supporting plate431 of the second mold portion 43. Bottom ends (as viewed in FIG. 7) ofthe second extending plates 435 abut against the extending portions 135of the evaporating plates 13, respectively; and inner sides of thesecond extending plates 435 contact the two sidewalls 133 from which theextending portions 135 extend. The other two sidewalls 133 contact innersides of the first extending plates 433, respectively. Bottom ends (asviewed in FIG. 7) of the extending portions 135, said other twosidewalls 133, and the first extending plates 433 are all coplanar withone another.

Referring to FIGS. 5 and 7, the supporting portions 15 are received inthe receiving holes 4151 of the protruding portion 415 of the first moldportion 41.

Referring to FIG. 7, the first mold portion 41 and the second moldportion 42 are then coupled together. In this state, the first pressingportions 414 of the first mold portion 41 contact the extending plates135 of the evaporating plate 13, respectively. The second pressingportions 416 press the bottom ends of said other two sidewalls 133 andthe first extending plates 433. The protruding portion 415 is spacedfrom the heat absorbing portion 131, while the supporting portions 15contact the heat absorbing portion 131. The sidewalls 133 of theevaporating plate 13 surround and are spaced from the protruding portion415. A second receiving chamber 50 is thus defined between theevaporating plate 13 and the first mold portion 41.

Referring to FIG. 8, copper powder is then filled in the secondreceiving chamber 50 and is sintered to form the second wick structure14. The supporting portions 15 also connect with the second wickstructure 14 by the sintering of the copper powder. In one embodiment,the supporting portions 15 become integrally connected with the secondwick structure 14.

After the first wick structure and the second wick structure 14 areformed, the first mold 20 and the second mold 40 are opened to obtainthe condensing plate 11 and the evaporating plate 13. The condensingplate 11 and the evaporating plate 13 are then attached together bywelding. The condensing plate 11 and evaporating plate 13 are broughtinto contact with each other, and then subjected to high temperature andhigh pressure for a period of time. As a result, the supporting portions15 penetrate through the first wick structure 12, with opposite ends ofthe supporting portions 15 thereby abutting against both the condensingplate 11 and the evaporating plate 13.

It is to be understood, however, that even though numerouscharacteristics and advantages of various embodiments have been setforth in the foregoing description, together with details of thestructures and functions of the embodiments, the disclosure isillustrative only, and changes may be made in detail, especially inmatters of shape, size, and arrangement of parts within the principlesof the disclosure to the full extent indicated by the broad generalmeaning of the terms in which the appended claims are expressed.

1. A plate-type heat pipe comprising: a condensing plate; an evaporatingplate engaged with the condensing plate to define a hermetic container;working fluid contained in the container; and a spherical supportingportion in the container sandwiched between and abutting against thecondensing plate and the evaporating plate.
 2. The plate-type heat pipeof claim 1, wherein a first wick structure is adhered on an innersurface of the evaporating plate, and the supporting portion extendsthrough the first wick structure.
 3. The plate-type heat pipe of claim2, wherein the evaporating plate comprises a heat absorbing portionadapted for contacting a heat source, a plurality of sidewalls extendingupwardly from edges of the heat absorbing portion, and a plurality ofextending portions extending outwardly from a plurality of thesidewalls, the extending portions hermetically connecting the condensingplate.
 4. The plate-type heat pipe of claim 3, wherein the first wickstructure is adhered on inner surfaces of the sidewalls and the heatabsorbing portion.
 5. The plate-type heat pipe of claim 4, wherein asecond wick structure is adhered on an inner surface of the condensingplate, and the supporting portion extends through the second wickstructure.
 6. The plate-type heat pipe of claim 5, wherein a peripheryof the second wick structure connects a periphery of the first wickstructure.
 7. The plate-type heat pipe of claim 1, wherein thesupporting portion is metallic.
 8. A method for manufacturing aplate-type heat pipe, the method comprising: a) providing a firstmetallic sheet, a second metallic sheet and a supporting portion; b)arranging the supporting portion between the first metallic sheet andthe second metallic sheet; and c) welding peripheries of the first andsecond metallic sheets together, thereby obtaining a hermeticalcontainer, the supporting portion inside the container and abuttingagainst the first and second metallic sheets.
 9. The method of claim 8,further comprising, before b), disposing the first metallic sheet is ina first mold and forming a first wick structure on the first metallicsheet by sintering a first powder.
 10. The method of claim 9, whereinthe first mold includes a first mold portion and a second mold portionmatching with the first mold portion, a cavity is defined between thefirst mold portion and the second mold portion, the first metallic sheetis received in the cavity and abuts against inner surfaces of the secondmold portion, and a first receiving chamber is defined between the firstmold portion and the first metallic sheet to receive the first powder.11. The method of claim 9, further comprising, before b), disposing thesecond metallic sheet in a second mold and forming a second wickstructure on the second metallic sheet by sintering a second powder. 12.The method of claim 11, wherein the second mold comprises a first moldportion and a second mold portion matching with the first mold portion,a cavity is defined between the first mold portion and the second moldportion, the second metallic sheet is received in the cavity and abutsagainst inner surfaces of the second mold portion, and a secondreceiving chamber is defined between the first mold portion and thesecond metallic sheet to receive the second powder.
 13. The method ofclaim 12, wherein a protruding portion protrudes from the first moldportion the second mold and extends towards the second metallic sheet,and the second receiving chamber is defined between the protrudingportion and the second metallic sheet.
 14. The method of claim 13,wherein a receiving hole is defined in the protruding portion, and thesupporting portion is received in the receiving hole and abuts againstthe second metallic sheet.
 15. The method of claim 14, wherein thesupporting portion becomes integrally connected to the second wickstructure when the second wick structure is formed.
 16. The method ofclaim 15, wherein during the welding, the first and second metallicsheets are subjected to high temperature and high pressure for apredetermined period of time and the supporting portion penetratesthrough the first wick structure to abut against the firstmetallicsheet.
 17. The method of claim 8, wherein the supporting portion ismetallic and has a spherical configuration.